The present invention relates generally to a low fat, vitamin/mineral fortified soy-based oral nutritional product useful for providing soy protein in addition to the inherent isoflavones to a health conscious population.
Substitution of vegetable protein for animal protein in an individual""s diet has traditionally addressed the needs of persons with food allergies or intolerance to dairy-based formula components (usually casein, whey, or lactose) and individuals who desire to limit or avoid animal protein for life style philosophy (vegetarianism) or religious beliefs and practices. As positive outcomes from research in the area of vegetable extracts in the nutritional management of disease states are published, desire to add these xe2x80x9cadded valuexe2x80x9d vegetables to individual diets has expanded in the general population.
Many of the xe2x80x9cactive componentsxe2x80x9d identified in vegetables are phytoestrogens. A number of these compounds have been identified in fruits, vegetables, and whole grains commonly consumed by humans. Phytoestrogens include isoflavones which occur in a variety of leguminous plants. Soybeans are the most significant dietary sources of isoflavones. Isoflavones have been detected and identified in biological fluids of humans consuming the plant material. Due to the phenolic structure, which is similar to those of animal estrogens, these compounds exhibit weak estrogenic properties and are termed phytoestrogens. It is the isoflavones which have received the most attention and have been reviewed in great detail in xe2x80x9cMammalian lignans and phyto-oestrogens- Recent studies on their formation, metabolism and biological role in health and diseasexe2x80x9d by Setchell and Adlercreutz, Role of the Gut Flora in Toxicity and Cancer. New York, Academic Press, 1988; pp 315-45; xe2x80x9cNaturally Occurring Oestrogens in Foods- A Reviewxe2x80x9d by Price and Fenwick, Food Additives and Contaminants, Vol.2, No.2, pp73-106,1985; and xe2x80x9cDietary Phytoestrogensxe2x80x9d by Kurzer and Xu, Annual Review of Nutrition Vol 17, 1997; pp 353-81.
Studies in humans, animals and cell culture systems suggest that dietary phytoestrogens play an important role in prevention of menopausal symptoms, osteoporosis, cancer, and heart disease. Proposed mechanisms include estrogenic and antiestrogenic effects, induction of cancer cell differentiation, inhibition of tyrosine kinase and DNA topoisomerase activities, suppression of angiogenesis and antioxidant effects. The major isoflavones occurring in plants are the glycosides of genistein, daidzein and glycitein.
Isoflavones isolated from soy have become the focus of much research in the areas of heart disease, cancer, osteoporosis and kidney diseases. This expanding knowledge in the possible role of soy and its fractions in the nutritional management of disease states has presented practical challenges for the average consumer in the market place. The primary challenge is access to good tasting products with naturally high concentrations of isoflavones.
The isoflavone contents in commercial soy raw ingredients vary depending on the levels of isoflavones in the plant variety and processing procedures. For example, approximately 90% of phytoestrogens present in soy foods are beta-glucoside conjugates of daidzein and genistein. However, in fermented soy products, the aglucones (unconjugated) are the predominant forms. The nutrient and isoflavone content of the most common available soy foods, soy ingredients and nutritionals are listed in Table 1 below.
While there are a few soy-based foods available on the market today, they are not easily incorporated into an individual""s diet. Accessibility of the products listed in Table 1 is an issue for most of the general population. A few of the products are starting to be stocked in standard grocery stores; however, many must be purchased in xe2x80x9cHealth Food Storesxe2x80x9d. More importantly, the taste and texture of soy products are objectionable to many individuals that have not grown up with soy protein in their diets. In addition, most of the foods in Table 1 are ingredients to be incorporated into a food dish and most individuals do not know how to cook with these ingredients. While the roasted soy nuts, which would probably be an acceptable snack food for most individuals, weigh in with a high isoflavone content, the high calorie and fat content are unacceptable for daily incorporation into an individual""s diet. Soy milk is a reasonable source of isoflavones and has been used by individuals with cow milk allergies for many years and there are currently more flavors and fat content options to chose from. A serving (1 cup) of xe2x80x9cLightxe2x80x9d soy milk contains 3 grams of fat and 8 grams of protein in 120 total calories. No inherent vitamins and a small amount of calcium and iron (2% of the RDI) are present in soy milk. A serving (1 cup) of full fat soy milk contains 4 grams of fat and 10 grams of protein in 140 total calories. The requirement for refrigerated storage and the flavor of soy milk remain a major obstacle for the average consumer.
FDA-regulated food products began using the Daily Value as the basis for declaring nutrient content May 8, 1994. Daily Values (DVs) are a set of dietary reference values to help consumers use food label information to plan a healthy overall diet. DVs actually comprise two sets of reference values for nutrients: Daily Reference Values (DRVs) and Reference Daily Intakes (RDI).
DRVs are a set of dietary references for which no set of standards previously existed. DRVs apply to fat, saturated fat, cholesterol, carbohydrate, protein, fiber, sodium and potassium. Based on 2,000 calories a day for adults and children over 4, the DRV for fat is 65 grams; saturated fat is 20 gm; cholesterol is 300 milligrams; total carbohydrate is 300 grams; fiber is 25 grams; sodium is 2,400 milligrams; potassium is 3,500 milligrams; and protein is 50 grams.
RDIs are a set of dietary references based on the Recommended Dietary Allowances (RDA) for essential vitamins and minerals. The name xe2x80x9cRDIxe2x80x9d replaces the term xe2x80x9cU.S. RDAxe2x80x9d(Recommended Daily Allowances). Recommended Dietary Allowances (RDA) are the set of estimated nutrient allowances established by the National Academy of Sciences used as the basis for setting the U.S.RDAs. It is updated periodically to reflect current scientific knowledge.
The liquid nutritional, Ensure(copyright) (Ross Products Division of Abbott Laboratories, Chicago, Ill.), a good tasting, shelf stable, ready to drink complete nutritional with a protein system that contains soy protein isolate, is an alternative to the more traditional soy foods. However, only 20% of the total protein system is soy protein isolate resulting in an isoflavone content too low to practically provide the benefit of consuming soy protein.
GeniSoy(trademark) is a powdered protein shake manufactured by GeniSoy Products Co. (Fairfield, Calif.) with water processed isolated soy protein. A serving (8 oz.) of the Vanilla product contains 14 gm of soy protein, zero fat and 18 gm of total carbohydrate in 130 calories. The vitamins and minerals are fortified at 25% of the RDI with the exception of vitamin E (170% of the RDI). GeniSoy Products literature states that although the isoflavone content of GeniSoy is not tested, typical isoflavone values for water processed soy protein isolate range from 1.0 to 5.0 mg of isoflavone/gram soy protein isolate. While this vitamin and mineral fortified product provides large amounts of soy protein isolate in a single serving, it is not a complete nutritional that could be used as a sole source of nutrition due to the absence of fat in the form of essential fatty acids. Further, the inconvenience of the powder form and the soy flavor remain an issue for many consumers.
Isoflavone compounds are associated with the inherent bitter flavor of soybeans. Consequently, in the production of commercial products, such as isolates and concentrates, the focus has been traditionally to remove these materials. For example, in a conventional process for the production of a soy protein isolate, in which soy flakes are extracted with an aqueous alkaline medium, much of the isoflavones are solubilized in the extract, and remain solubilized in the whey, which is usually discarded following acid precipitation of the protein to form an isolate. Residual isoflavones left in the acid precipitated protein isolate are usually removed by exhaustive washing of the isolate. This process has been modified to maintain and enrich the isoflavone content of the vegetable isolates, concentrates, protein fiber and whey.
EP 0 647 408 by Shen, et al., teaches how to manufacture an isoflavone enriched vegetable protein isolate by extracting a vegetable protein material containing isoflavones at a pH above the isoelectric point of the material, then adjusting the pH to about the isoelectric point of the protein material resulting in a precipitate, then doing limited washing of the precipitate to provide an isoflavone enriched protein isolate.
U.S. Pat. No. 5,637,562 by J. L. Shen discloses a process to manufacture isoflavone enriched vegetable protein concentrate through an isoelectric wash of a vegetable protein material to provide a protein concentrate, which is slurried and reacted with a sufficient amount of beta-glucosidase enzyme or esterase enzyme for a time period, temperature and pH sufficient to convert at least a majority of the glucone isoflavones contained in the concentrate to aglucone isoflavones.
U.S. Pat. No. 5,352,384 by J. L. Shen discloses a process to manufacture isoflavone enriched vegetable protein fiber. The starting material is extracted at a pH above the isoelectric point of the protein material, the aqueous slurry containing the solubilized isoflavones is reacted with a beta-glucosidase to convert the isoflavones in glucone form to an aglucone isoflavone making the isoflavones less soluble, the fibrous residue is recovered to provide a vegetable fiber product which has been enriched with aglucone isoflavones.
U.S. Pat. No. 5,637,561 by J. L. Shen discloses a process to make aglucone isoflavone enriched vegetable protein whey by treating the whey stream, comprising glucone isoflavones, with a sufficient amount of beta-glucosidase enzyme or esterase enzyme or acid to convert at least a majority of the glucone isoflavones to aglucones thereby providing an aglucone enriched whey stream. The aglucone enriched whey protein is obtained by recovery of the protein.
The importance of isoflavone enriched vegetable protein sources becomes more apparent when one reviews the field of isoflavone research. Most of the human research on isoflavones has been carried out by incorporating soy products into the typical American diet or studying Asian countries where soy is a normal part of the diet. While the health benefits of soy have been attributed to isoflavones, the actual active ingredient or ingredients have yet to be identified. The level and ratio of the isoflavones in addition to other inherent components of soy may play an important role in the health benefits attributed to soy. However, there are dietary supplement patents incorporating isolated phytoestrogens into compositions for the management of osteoporosis and premenstrual syndrome.
A product containing isoflavones for the management of osteoporosis is described in U.S. Pat. No. 5,424,331 by M. Shlyankevich which discloses a pharmaceutical or dietary supplement for the treatment or prevention of osteoporosis. The composition comprises phytoestrogen compounds; dried licorice root extract; calcium, magnesium and zinc salts; beta carotene; and vitamin D and E in an acceptable inert carrier.
A product containing isoflavones for the management of premenstrual syndrome is described in U.S. Pat. No. 5,569,459 by M. Shlyankevich which discloses a pharmaceutical or dietary supplement for controlling the stimulation of estrogen production. The composition comprises phytoestrogen compounds; dried licorice root extract; a sedative selected from the group consisting of Balerian root dry extract, passion flower dry extract and Ginseng root powder; beta-carotene; pyridoxine hydrochloride; Vitamin E; calcium, magnesium and zinc salts; coumestan; and pantothenic acid in an acceptable inert carrier.
A dietary supplement for supplementing the nutritional needs of women and preventing or reducing life stage associated health risks during each of their principal adult life stages (pre-perimenopause, perimenopause and menopause, or post-menopause) is described in U.S. Pat. No. 5,654,011 by S. D. Jackson, et al. The dietary supplement comprises calcium, magnesium, boron, copper, manganese, zinc, vitamin D, E and C; iron, folic acid, vitamin B12 and B6; chromium, and phytoestrogens in a biologically acceptable carrier.
As discussed above, there are several soy-based products currently available to the consumer. However, they are products with unacceptable taste or mouth feel, they require special storage conditions such as refrigeration or are in powder forms requiring an additional reconstitution step before consumption. Further limitations of these products appear in their nutrient content. Their nutrient content ranges from no supplementation of vitamins and minerals to fortification at 25% of the RDI. These soy based products have not been optimized to complement the positive effects attributed to soy such as, for example, fortification of the formula to provide a calcium/phosphorous ratio sufficient to complement the effects of soy on osteoporosis; or a sodium limitation for the hypertensive individual; or an antioxidant package to complement the cancer and heart disease benefits of soy.
Clearly, there is need for a convenient, shelf stable, low fat, calcium enriched, good tasting, complete nutritional which is a soy-based product that will deliver inherent isoflavones to an individual choosing to supplement their diet with soy protein.
The present invention relates generally to a shelf stable, low fat, vitamin and mineral fortified soy-based complete liquid nutritional product useful for providing soy protein and its inherent isoflavones to an individual.
One aspect of the invention is a complete liquid nutritional product containing a protein system providing from about 17% to about 25% of the total calories of the product, preferably from about 19% to about 23% of the total calories of the product; a lipid system which provides from about 5% to about 15% of the total calories of the product, preferably from about 10% to about 14% of the total calories of the product; a carbohydrate system which provides from about 56% to about 68% of the total calories of the product, preferably from about 57% to about 65% of the total calories of the product; and a vitamin and mineral system in quantities sufficient to make the product a complete nutritional, preferably at least 20% of the RDI in a single serving. The liquid nutritional product has a caloric density from about 0.6 kcal/ml to about 1.1 kcal/ml, preferably from about 0.8 kcal/ml to about 1.0 kcal/ml.
The protein system contains from about 30% to 100% (% wt.) soy protein, preferably from about 50% to 100% soy protein. The soy protein is selected from the group including soy flakes, soy protein isolate, soy protein concentrate, hydrolyzed soy protein, soy flour, soy protein fiber, soy whey and mixtures thereof. Preferably, the soy protein comprises at least 0.7 mg isoflavones/gm soy protein and at least 0.5 mg genistein 1 gm soy protein, more preferably at least 1.2 mg isoflavones/gm soy protein and at least 0.8 mg genistein 1 gm soy protein.
The lipid system may be selected from the group including high oleic safflower oil, soy oil, fractionated coconut oil, high oleic sunflower oil, corn oil, canola oil and mixtures thereof. Preferably, the lipid system is a blend of 20% corn oil, 40% high oleic safflower oil and 40% canola oil.
The carbohydrate system may be selected from the group including hydrolyzed corn starch, maltodextrin, glucose polymers, sucrose, corn syrup solids, glucose, fructose, lactose, high fructose corn syrup, fructooligosaccharides and mixtures thereof. Preferably, the carbohydrate system comprises from about 35% to 52% of total carbohydrate as corn syrup, from 0 to about 22% of total carbohydrate as maltodextrin and from about 43% to 48% of total carbohydrate as sucrose, more preferably, from about 35% to 40% of total carbohydrate as corn syrup, from 15% to about 22% of total carbohydrate as maltodextrin and from about 43% to 45% of total carbohydrate as sucrose.
The vitamin and mineral system for this complete nutritional comprises the vitamins A, B1, B2, B6, B12, C, D, E, K, beta-carotene, Biotin, Folic Acid, Pantothenic Acid, Niacin, Choline; the minerals calcium, magnesium, potassium, sodium, phosphorous, chloride; the trace minerals iron, zinc, manganese, copper, iodine; and the ultratrace minerals chromium, molybdenum and selenium. Preferably the calcium is fortified at 35% of the RDI in a single serving.
A second aspect of the invention is a method for providing soy protein containing inherent isoflavones, specifically genistein, to an individual by feeding the liquid nutritional product described above.
During the process of formulating the soy-based nutritional of the invention, unexpected stability challenges were addressed. A third aspect of the invention is the method of stabilizing a calcium enriched soy-based nutritional. The calcium enriched soy-based product comprises an isoflavone enriched soy protein, calcium fortified at 35% of the RDI with no more than 100 ppm soluble calcium and a stabilizer system to help suspend the insoluble minerals. Insoluble calcium sources are preferred to prevent the destabilization during sterilization of the soy protein by the soluble divalent minerals. Preferably the insoluble calcium sources are selected from soy-protein-bound-calcium and calcium citrate. More preferably, the soy-protein-bound-calcium contributes 85% of the total calcium and calcium citrate contributes 14% of total calcium. The stabilizer system consisting of cellulose gel and carrageenan provides for suspension of minerals; improved product physical stability; and improved organoleptic characteristics. Preferably, the stabilizer system comprises from about 1500 to about 2500 ppm cellulose gel and from about 150 to about 300 ppm carrageenan.
The stabilizing method further comprises the selection of a carbohydrate system consisting of maltodextrin, corn syrup and sucrose which expands the final product pH range of stability (6.6 to 7.2) while optimizing final product mouth feel. This carbohydrate system provides for a more durable formulation that can adapt to the variability seen in the stability of isoflavone enriched soy protein sources. The preferred carbohydrate system comprises from about 35% to about 52% of total carbohydrate as corn syrup, from 0 to about 22% of total carbohydrate as maltodextrin and from about 43% to about 48% of total carbohydrate as sucrose. Other aspects of the invention are described throughout the application.
The nutritional products of this invention may also be manufactured with organic/natural ingredients. A natural or organic product complements the health benefits of the soy protein/isoflavones. Attention to the way the source material is grown, processed and handled identifies the ingredients allowed in a natural or organic product.
Any reference in this patent application to the xe2x80x9cRDI for vitamins and mineralsxe2x80x9d refers to the list published in the 1993 Federal Register, Vol. 58. RDIs are a set of dietary references based on the Recommended Dietary Allowances (RDA) for essential vitamins and minerals. The name xe2x80x9cRDIxe2x80x9d replaces the term xe2x80x9cU.S. RDAxe2x80x9d(Recommended Daily Allowances). Recommended Dietary Allowances (RDA) are the set of estimated nutrient allowances established by the national Academy of Sciences used as the basis for setting the U.S.RDAs. It is updated periodically to reflect current scientific knowledge.
The term xe2x80x9ctotal caloriesxe2x80x9d refers to the total caloric content of a predetermined volume of the finished nutritional product. For example, a product with 12.5 gm of protein, 3 gm of fat and 33 gm of carbohydrate has 209 total calories per 237 ml.
The term xe2x80x9cisoflavonesxe2x80x9d refers to the compounds having the following general formula, with specific compounds identified in Table 2.
As described in Table 2, daidzin, genistin and glycitin are the beta-glucoside conjugate (glucones) moieties. Daidzein, genistein and glycitein are the unconjugated (aglucones) moieties. As used herein xe2x80x9cdaidzein, genistein and glycitein levelsxe2x80x9d include both the conjugated and unconjugated moieties. The typical ratio of genistein to daidzein to glycitein in soy protein is 67 to 30 to 3.
The term xe2x80x9csoy protein or soy protein sourcexe2x80x9d refers to any protein form isolated from soybeans including, for example, soy flakes, soy protein isolate, soy protein concentrate, hydrolyzed soy protein, soy flour and soy protein fiber.
The term xe2x80x9cstandard genisteinxe2x80x9d soy protein refers to soy proteins that contain from about 0.5 to about 1.0 mg genistein per gram of soy protein.
The term xe2x80x9chigh genistein soy proteinxe2x80x9d and xe2x80x9cisoflavone enriched soy proteinxe2x80x9d refers to soy proteins that contain at least 1.0 mg genistein per gram of soy protein.
The term xe2x80x9ctotal isoflavone contentxe2x80x9d refers to the total amount of genistein, daidzein, glycitein and their glucoside moieties.
The term xe2x80x9ccomplete nutritionxe2x80x9d refers to a product that may be used as the sole source of nutrition. A complete nutritional provides 8 to 14 gm of protein; 3 to 10 gm fat; 30 to 40 gm carbohydrate; and 20 to 40% of the RDI for vitamins and minerals in 8 fl. oz or about 240 ml.
The term xe2x80x9csingle servingxe2x80x9d refers to approximately 8 fl. oz or about 240 ml.
The term xe2x80x9cgenetically engineered xe2x80x9d or xe2x80x9cgenetically modified organismsxe2x80x9d (GMO) refers to ingredients made by techniques that alter the molecular or cell biology of an organism by means that are not possible under natural conditions or processes. Genetic engineering includes recombinant DNA, cell fusion, micro- and macro-encapsulation, gene deletion and doubling, introducing a foreign gene, and changing the positions of genes. It shall not include breeding, conjugation, fermentation, hybridization, in-vitro fertilization and tissue culture.
It is a principal object of the invention to provide an improved soy-based food for individuals who wish to add soy to their diets. The invention is to provide a shelf stable, low fat, good tasting liquid food composition which utilizes a soy protein system containing inherent levels of isoflavones, provides antioxidants and is a good source of calcium. Another object of this invention is to provide a method for stabilizing a calcium enriched soy-based nutritional.
The nutritional formulas of this invention will typically provide the following caloric distribution. The protein system will typically provide from about 17% to about 25% of total calories, more preferably from about 18% to about 24% of total calories. The fat system will provide from about 5% to about 15% of total calories, more preferably about 10% to about 14% of total calories. The carbohydrate system will typically provide from about 56% to about 68% of total calories, more preferably from about 57% to about 65% of total calories. The caloric density is typically from about 0.60 kcal/ml to about 1.10 kcal/ml, preferably from about 0.80 kcal/ml to about 1.0 kcal/ml.
One component of the nutritional formula of this invention is soy protein. As described above, a number of soy protein sources may be considered. The soy protein is isolated from the soybean. The soybean is an excellent source of high quality protein where about 38% to 40% of the soybean is protein. Briefly (as shown in Scheme I), the processing of soybeans involves the extraction of the oil from the dehulled, and cracked soybeans leaving the defatted soybean flakes. 
The defatted soybean flakes are typically milled into flours; alcohol-extracted or alkoline/H2O extracted to remove flavor compounds and sugars to make protein concentrates; and processed with water to remove sugars and flavor compounds, precipitated and dried to make protein isolates. Whey and protein fiber are by-products of the above processes. The preferred soy protein is processed in a manner to enrich the isoflavone content so that total isoflavone content (glucone and aglucone forms of genistein+daidzein+glycitein) is at least 0.7 mg isoflavones/gram soy protein. Further, the genistein content of the soy protein is at least 0.5 mg genistein/gram soy protein. Acceptable soy protein sources are listed in the attached Examples. Preferred methods to produce isoflavone enriched vegetable protein were discussed briefly in the Background when reviewing production methods of isoflavone enriched soy protein described in EP 0 647 408, U.S. Pat. No. 5,637,562, U.S. Pat. No. 5,352,384, and U.S. Pat. No. 5,637,561 all by J. L. Shen.
The method used to analyze isoflavones in the final product utilizes the published extraction procedure of Murphy et al., Isoflavones in Soy-Based Infant Formulas, Journal of Agricultural and Food Chemistry, Vol 45, 1997, pp. 4635-4638. The non-polar nature and the intense UV absorptivities of these compounds make reversed phase HPLC a suitable approach for their determination in a variety of foods. An acidic 50/50 acetonitrile/water solution is used to extract the isoflavones from lyophilized product. The filtered extract is diluted with a buffered beta-glucuronidase solution, which rapidly affects the conversion of all conjugated forms (the xe2x80x9cgluconesxe2x80x9d) of each isoflavone to the unconjugated form (the xe2x80x9cagluconesxe2x80x9d daidzein, genistein and glycitein). The aglucones are then separated by reversed phase chromatography, and detected by UV absorbance at 250 nm (daidzein) and at 262 nm (genistein). The aglucone concentrations are then determined by peak area proportionation versus solutions of specialized chemical reference standards of known concentrations. Glycitein values are estimated from the genistein standard response at 262 nm as there is no glycitein standard available.
Soy proteins enriched with isoflavones have proven to be less heat stable than the regularly processed soy protein. The presence of soluble divalent minerals in the final product destabilizes the protein upon terminal sterilization. Consequently, the preferred soy protein source contains calcium in a colloidal suspension with the protein. U.S. Pat. No. 4,642,238 by H. C. Santz, et al., teaches how to produce a mineral enriched protein by combining a hydrated gel of an alkaline earth salt with soy protein isolate to form a mineral enriched soy protein composition. Preferably, about 85% of the total calcium is contributed by calcium bound to the soy protein and about 14% of total calcium is supplied by calcium citrate (insoluble calcium). Soluble calcium levels are no more than about 0.1% (100 ppm), preferably no more than 0.01% (10 ppm). Soluble calcium levels over 100 ppm destabilize the soy proteins during terminal sterilization.
A natural or organic version of the nutritional products of this invention incorporates soy protein isolated from non-GMO soy beans.
The second component of the nutritional products of this invention is the fat system. As stated above, from about 5% to about 15% of the total calories of the nutritional products of the present invention are provided by this fat system. Any of the typical fat sources could be used such as high oleic safflower oil, soy oil, fractionated coconut oil, high oleic sunflower oil, corn oil, canola oil and mixtures thereof. The preferred fat system is a blend of 40% high oleic safflower, 40% canola oil and 20% corn oil. This fat blend, at these levels, permits the product to meet the recommendations of the American Heart Association for less than 30% of total dietary calories from fat, less than 10% of total calories from saturated fat, and no more than 10% of total calories from polyunsaturated fat. This blend also meets the recommendation of a ratio of n-6 to n-3 fatty acids of between 4:1 and 10:1. The lipid system will also typically contain a blend of oils designed to provide all of the essential fatty acids required to prevent malnutrition. The essential fatty acid, linoleic acid, can be provided by incorporating canola oil and soy bean oil into the formula. Other sources of these essential fatty acids are well known in the art and include borage, black currant seed, corn, marine oils, fungal oils, safflower, high oleic safflower, sunflower, high oleic sunflower, evening primrose, cottonseed, rice bran, grapeseed, flaxseed, garlic, peanuts, almonds, walnuts, wheat germ, egg, and sesame. To avoid essential fatty acid deficiency issues with sole source nutrition applications, the levels of linoleic acid (1 8:2n6) were chosen to deliver about 1 to about 3% of total energy based on a volume of nutritional product of about 1500 ml.
A natural or organic version of the nutritional product of this invention will incorporate the fat sources listed above, where said fat sources have been extracted according to non-chemical means, for example mechanically pressed (expeller pressed), hydraulic pressed, or stone pressed. Mechanical pressing, also known as expeller pressing, removes oil through the use of continuously driven screws that crush the seed or other oil-bearing material into pulp from which the oil is expressed. In addition to a preferred extraction method for the fats of a natural or organic nutritional product, the starting material are non-GMO sources.
The third component of the nutritional products of this invention is a source of carbohydrates. The carbohydrates that may be used in the nutritional formula can vary widely. Examples of suitable carbohydrates that may be utilized include hydrolyzed corn starch, maltodextrin, glucose polymers, sucrose, corn syrup solids, glucose, fructose, lactose, high fructose corn syrup and fructooligosaccharides.
As noted above, the carbohydrates provide from about 56% to about 68% of the total calories of formula. Any single carbohydrate listed above, or any combination thereof, as appropriate may be utilized to provide these calories. The preferred carbohydrate system has been designed to optimize protein stability, mouth feel, and balance the palatability of the nutritional formula with the total calories contributed by simple sugars. The preferred carbohydrate source is a 35% of total carbohydrate corn syrup/22% of total carbohydrate maltodextrin mixture with 43% of total carbohydrate as sucrose.
Maltodextrins and corn syrup solids are complex carbohydrates routinely used in nutritional formulations because of their excellent digestibility and functional properties. Specifically, they are good water binders and provide products with desired texture and mouth feel. Maltodextrins are polysaccharides obtained from the acid or enzyme hydrolysis of corn starch. Their classification is based on the degree of hydrolysis and is reported as dextrose equivalents (DE). The FDA defines maltodextrins as non-sweet, nutritive polysaccharides that have a DE less than 20. Corn syrup solids are defined as having DE""s greater than 20. Corn syrup solids consist of dextrose chains about 3 to 4 units long while the maltodextrin used in the present invention (Lodex 15) is less hydrolyzed and contains polymers of 5 to 6 dextrose units. Polymer length is a major difference between corn syrup (DE 29) and Lodex 15 (DE 18). The difference in polymer length results in different functionality.
In the present invention, the use of corn syrup as a partial substitute for the maltodextrin results in a product that remains stable over a broader pH range. Specifically, product with corn syrup from about 35% to about 52% of the total carbohydrates was very stable from a pH range from about 6.6 to about 7.2. The broader pH range provides for a more durable formulation that can easily accommodate stability variability in the isoflavone enriched soy protein.
Substitution of corn syrup for maltodextrin to maximize product stability negatively impacts product mouth feel. Maltodextrins are often used as fat replacers because of their ability to provide texture and mouth feel. These sensory attributes are diminished when the maltodextrin is completely replaced by corn syrup but to a much less extent when only partially substituted as in the preferred carbohydrate blend.
A natural or organic version of the nutritional products of this invention incorporates carbohydrates isolated from non-GMO sources. Natural Sugars distributed by Florida Crystals (Palm Beach, Fla.) is a minimally-processed natural sugar source. The juice is pressed from freshly-cut sugarcane, washed, filtered and crystallized. The product contains no artificial additives or preservatives.
The fourth component of the nutritional products of the present invention includes supplemented vitamins and minerals. The vitamin and mineral profile provides 20% to 30% of the RDI for vitamins and minerals in a single serving. Preferably, the nutritional products are designed so that two eight fluid ounce servings, approximately 480 ml, will provide at least 50% of the recommended daily intake (RDI) of vitamins and minerals.
The vitamin and mineral system for the complete nutritional of the invention comprises the vitamins A, B1, B2, B6, B12, C, D, E, K, beta-carotene, Biotin, Folic Acid, Pantothenic Acid, Niacin, and Choline; the minerals calcium, magnesium, potassium, sodium, phosphorous, and chloride; the trace minerals iron, zinc, manganese, copper, and iodine; and the ultratrace minerals chromium, molybdenum, selenium. Desirably, the nutritional products will include antioxidants such as a combination of beta-carotene, vitamin E and C at about 50% of the RDI per single serving.
Further the preferred nutritional product provides about a 1:1 ratio of calcium (35% of the RDI) to phosphorus (30% of the RDI) per single serving. Such high levels of calcium and phosphorus are achieved without compromising physical stability (destabilization of protein) by using a soy protein in which the calcium is bound to the protein (insoluble calcium) in combination with other sources of insoluble calcium. The preferred soy protein source contains calcium in a colloidal suspension with the protein. U.S. Pat. No. 4,642,238 by H. C. Santz, et al., teaches how to produce a mineral enriched protein by combining a hydrated gel of an alkaline earth salt with soy protein isolate to form a mineral enriched soy protein composition. Preferably, about 85% of the total calcium is contributed by calcium bound to soy protein and about 14% of total calcium is supplied by calcium citrate (insoluble calcium). Soluble calcium levels of more than about 0.1% (100 ppm or more) destabilizes the proteins during terminal sterilization.
The use of synthetic vitamins, minerals and/or accessory nutrients in products labeled as organic are limited to that which is required by regulation or recommended for enrichment and fortification by independent professional associations. xe2x80x9cAccessory nutrientsxe2x80x9d refer to nutrients not specifically classified as a vitamin or mineral but found to promote optimal health. Examples include omega-3 fatty acids, inositiol, choline, isoflavones and taurine.
Suspension of insoluble minerals, product stability and mouth feel is further improved by using one or more stabilizers. Useful stabilizers include, but are not limited to, cellulose gel and carrageenans. The stabilizer system comprises from about 1,000 to about 5,000 ppm cellulose gel, more preferably from about 1,500 to about 2,500 ppm cellulose gel and from about 100 to about 600 ppm carrageenan, more preferably from about 150 to about 300 ppm carrageenan. This combination of stabilizers will result in a viscosity ranging from about 10 to about 100 centipoise (cps), more preferably from about 20 to about 45 cps.
The nutritional products of the present invention will also desirably include a flavoring and or color to provide the nutritional products with an appealing appearance and an acceptable taste for oral consumption. The flavor systems cover or work with the beany/nutty/bitter notes apparent in soy protein. Useful flavorings include, for example, strawberry, butter pecan, chocolate, banana and vanilla.
Natural flavors are materials which are comprised of flavor compounds derived from natural bases (typically botanicals such as herbs, spices, fruits or compounds derived from fermentation), a non-synthetic carrier (ethanol, propylene glycol, etc.), and agents which help preserve the natural flavors (grain ethanol, non-synthetic glycerin, non-synthetic acetic acid) The natural constituents included in the natural flavor are extracted using a number of natural and synthetic solvents. The solvents are removed by evaporation with the final flavor compounds including trace amounts of the solvents (typically less than 10 ppm). The number of flavor compounds comprising natural flavors vary, but may number up to 100 or more. A natural or organic version of the nutritional products of this invention incorporates natural flavors.
The nutritional products of this invention can be manufactured using techniques well known to those skilled in the art. While manufacturing variations are certainly well known to those skilled in the nutritional formulation arts, a few of the manufacturing techniques are described in detail in the Examples. Generally speaking an oil blend is prepared containing all oils, any emulsifier, and the fat soluble vitamins. Two more slurries (carbohydrate and protein) are prepared separately by mixing the carbohydrate and minerals together and the protein in water. The two slurries are then mixed together with the oil blend. The resulting mixture is homogenized, heat processed, standardized with water soluble vitamins, flavored and the liquid terminally sterilized or dried to produce a powder. The formula can be sterilized and subsequently utilized on a ready-to-feed (RTF) basis or stored in a concentrated liquid or a powder form.